In general, catheters are used in medical procedures in which tubular structures, lumens, pleural cavities or spaces of the body, such as airways, vessels, organs and joints, are diagnostically examined and/or therapeutically treated. Catheters, which can be introduced into the body through a natural orifice or through an incision, can deliver imaging devices, surgical instruments, implants, fluids, drugs, pharmacologic materials, biologic materials, biologic agents and therapeutics to treat or remedy various pathologies found therein. Catheters also guide and deliver other components, such as guide wires, scaffolds and tools, to the intended site within the body.
Flexible, semi-rigid and rigid endoscopes are widely used in medicine to provide direct visualization for diagnostic and therapeutic purposes. Flexible, semi-rigid and rigid endoscopes are available in many sizes and configurations intended for use in different parts of the body and for a variety of diagnostic and therapeutic procedures. The visualization device (i.e., a fiber optic image bundle or a sensor at the distal tip of the device), together with the means for illumination, are an integral part of the endoscope. Endoscopes may also provide working channels to guide and deliver other instruments to the desired site. Endoscopes and endoscopic systems are, currently, a reusable and expensive resource in a physician's armamentarium. In addition, the endoscopic equipment systems required to operate endoscopes are often large, bulky and relatively immobile devices.
A limitation in the utility of the flexible endoscope is that their outer diameters are often too large, their inner ‘working channel’ diameters are often too small, and their lengths are often inadequate to appropriately diagnose and treat the anatomy and corresponding pathologies found in the far reaches of the body's organs, vessels and spaces. A further limitation of the utility of the flexible endoscope is that the articulation of the distal tip, and thus, its maneuverability, is typically accomplished by complicated mechanical structures that control the manipulating of the flexible endoscope's distal tip. As such, the maneuverability is limited by the capabilities of the mechanical structures. In addition, optimizing the external and internal diameters of the flexible endoscope is limited by the size and requirements of the mechanical structures.
There are several streerable catheter and guidewire devices known in the art. For example, U.S. Pat. No. 6,579,246 to Jacobsen et al. describes a guidewire system for introduction into bodily lumens having a distal section with a core wire with a tapering profile, with a coil disposed over the core wire, and a micromachined tube with a plurality of cuts coupled to the coil. The guide wire is maneuvered into bodily cavities by torque exerted on the proximal end of the wire, wherein the distal section with micromachined tubing is capable of bending away from the cavity walls. The International Publication No. WO 2013/017875 to Ataollahi et al. describes a catheter device having a steerable tip made with a plurality of stacked segments having a carbon fiber backbone and helical cuts therein. The streerable tip can be bent in a range of directions via guide tendons extending through the steerable tip. U.S. Pat. No. 7,637,903 to Lentz et al. describes a catheter having an articulation segment with tube having sections with variously oriented slits. The articulation segment allows for the catheter to coil in a plurality of directions and planes.
However, the steerable catheters described above suffer from a number of disadvantages. First, the structure of the known devices described above are still rather complex, requiring complicated mechanical structures to maneuver the devices. Additionally, while these known devices provide for means to bend sections of the catheter or guidewire body, they do not provide reinforced structures to avoid kinking of the catheter or guidewire body during insertion into bodily cavities. Furthermore, it is often desirable to be able to only bend the catheter tip in a single plane to provide for more precise maneuvering of the catheter. The devices described above are disadvantageous because, while they provide for articulation in a plurality of directions, it is not possible to limit the bending direction to only one plane.
What is desired, therefore, is a steerable catheter that can be steered through bodily cavities using a flexing tip member that provides a simple and accurate steering mechanism. What is also desired is a steerable catheter with a catheter body rigid enough to avoid kinking during insertion into body cavities, and that is able to make very tight turns with a short, steerable distal section and where the diameter of the catheter is as small as possible. What is also desired is a steerable catheter with an imaging device that is capable of providing a focused image regardless of how close the imaging device is positioned to target tissue. What is further desired is to have the above described catheter that can be manufactured at low cost as a disposable product.